For industrial assembly automation applications, vibratory bowl feeders are commonly used to automatically feed individual components (e.g. electronic devices manufactured using Wafer-level packaging) along semiconductor packaging and assembly lines. Presently, electronic devices to be fed by such vibratory bowl feeders are typically fed in a sequential queue, and separated from other electronic devices in the queue by using hard stoppers and/or vacuum suction at the end of a feeding track before being removed by a pick head. However, because the electronic devices tend to be rather fragile devices with brittle edges, it has been observed during the process of transferring them from the feeding track that collisions of said edges of the electronic devices with the feeding apparatus may frequently result in unacceptable chipping. From investigations, it has further been found that the front edge of a conventional separator (such as that found in a vibrational bowl feeder) is usually the cause of such chipping. Needless to say, such electronic devices with chipped edges are defective and have to be discarded, undesirably lowering effective yield and increasing overall costs of production.
To illustrate the problem, referring to FIGS. 1A and 1B depicting a conventional feeding apparatus 100, electronic devices 102 carried on a guide track 104 are fed to a separator 106. The guide track 104 and the separator 106 are typically separated by a small gap 108, such that each electronic device 102 must be made to cross the gap 108 when being transferred from the guide track 104 to the separator 106. Thereafter, the transferred electronic device 102 sits on the separator 106 until it is picked up by a pick head (not shown). Since the electronic device 102 is physically rather small, the electronic device 102 may tilt slightly (at its front end) during its transfer from the guide track 104 to the separator 106 (see FIGS. 2A and 2B). As a result, a lower front edge of the electronic device 102 and associated corners thereof may collide against an edge of the separator 106 during the transfer. Undesirably, this may consequently cause the lower front edge or corners of the electronic device 102 to be chipped, thus rendering the damaged electronic device 102 defective and it has to be discarded.
One object of the present invention is therefore to seek to lower the risk of damage to electronic devices 102 when they are being transferred from the guide track 104 to the separator 106.
These and other aspects of the invention will be apparent from and elucidated with reference to the embodiments described hereinafter.